Advances in communication technology have made it easier to communicate information between computer systems and/or devices connected to different communication networks. When transferring information between different networks it is often important that the transfer of information occurs in a secure manner. In some computing and communication environments that include multiple networks, such information security can be obtained by physically isolating each individual network. For example, secured networks or devices used by the United States Department of Defense are typically physically isolated from all other unsecured networks.
However, in certain work environments, it may be necessary for a secured network to collect data from an unsecured network. For example, in a defense environment, it may be necessary to have a computer system or device used in a secured network that can receive information from an unsecured network. There are also commercial applications where companies dealing with sensitive information may require one or more computers in their network to be connected to an unsecured network or the Internet.
Data diodes have been used to provide information security when transferring information between an unsecured network and a secured network. The data diode can be connected between different networks and will only allow data to travel in one direction. For example, the secured network can receive data from the unsecured network via a data diode, but the unsecured network cannot receive data from the secured network.
Data diodes typically require an external voltage source to operate. Unfortunately, it may be impossible or inconvenient to obtain power from external voltage source under certain conditions.